A self-piercing tap of this kind is known from DE 44 08 817 C1, comprising a plastic housing which is provided with a branch connection member and in which a valve is inserted with the help of a plurality of sealing rings, both between the housing and the valve as well as between the components of the valve. The branch sleeve projecting into the branch connection member is designed as a separate part. A tap of this kind comprises a complicated construction and is lavish during assembly. The sealing rings are subjected to aging and, thus, become leaky.
It is the object of the invention to provide a valve self-piercing tap which essentially avoids the use of sealing rings that are separately to mount and which is of simple design and mounting.